regex的使用方法，請給齣實際例子

例子：
var
  AFile: TStrings;
  S: string;
const
  title = '<title>.*?</title>';
begin
  AFile := TStringList.Create;
  AFile.LoadFromFile('F:\Content.txt');
  with TRegExpr.Create do
  try
    Expression := title;
    if Exec(AFile.Text) then
    begin
      S := Match[0];
      S := Copy(S, 8, Length(S)-7-8);
      ShowMessage(S);
    end;
  finally
    AFile.Free;
    Free;
  end;
end;